Apparatus for sealing oil wells



March 9 1926.

W. T. THOMAS Original Filed April 9 @atented o d,

j en ire Application filed April e,

To all whom it may concern:

Be it lmown that 1, WILLIAM T. THOMAS, a citizen of the United States, residing at Tonkawa, in the county of Kay and State of Uklahoma, have invented certain new and useful improvements in Apparatus for idealingOil Wells, of which the following is a specification, reference being had to the accompan drawings.

This invention relates to apparatus for sealing oil wells and more particularly to a paratus for use in cementmg the casings o wells to the walls of the well.

An important object of the invention is to rovide an element acting as a iston for riving the cement out of the casing at the bottom so that it will rise about the walls of the casing and means for locking this 'iston at a predetermined point in the cas mg so that a predetermined level of the cement may be ad both interiorly and on teriorly of the casing.

A still further object of the invention is to rovide a device of this character in which the iston is automatically locked and in this loo 'ng acts a cylinder valve periectly cutting 0E return of the cement to the casing.

A still further object of the invention is the rovision of a device of this character whic may bereadily removed from the well after the sealing apparatus has been operated. These and other objects I attain by the construction shown in the accompanying drawings, wherein for the gurpom of illustra'tion is shown a preierre embodiment of my invention and wherein Figure 1 is a fragmentary section of the lower portion of a well showing apparatus to constructed in accordance with my invention in the position assumed after the combined piston and valve is seated;

Figure 2 is a bottom plan view oi thevalve disk; and

Pi re 3 whic the dish is integrally constructs the coupling for the casing sections.

Reierrins now-more particularly to the drawings, the numeral 10 generally indicates here 11 a casing within the bore.

shows a modified construction in d with OF TON WA, OKLAHOMA, ASSIGNOB'OE' ONE-H TO A; INCL, 0F TONKAWA, OKL

a. FOB- SEALING GE 8.

wet, Serial no. 22,000. Renewed January 14, was.

In accordance with my invention, this caslng adjacent its lower end is provi a coupling 2 throughout its length and within which the adjacent sections of the casing in an.engage-' ment leave exposed a portion of the threads, as indicated at 13. con ling at this exposed section 13 is a disk 1 aving a central opening 15 tapered to prov1de an upwardly facing valve seat. To the under surface of the valve seat, springs 16 of a desired number are secured and ex tend inwardly and downwardly as "shown and have their lower ends 17 pointed and arranged upon a circumference less than the size of the opening of the valve seat.

A follower or piston is provided comprismg a cup-shaped member 18 having at its lower end a teat 19, the lower extremity of which is pointed, as at 20, so that it may readily enter the opening 15 of the disk 14. The upper end of the teat at the point where it 1o1ns the cup-shaped member 1s shaped to form a valve 21 for coaction with the seat and the teat intermediate its ends is provided with ratchet threads, shoulders of these threads facing upwardly. This cup-shaped piston is of a size as closely approximate as is possible the internal diameter of the casing and is provided inteq riorly with screw threads 23.

1OMA', A oonrorrorras indicated at 22, the

ded with 12 which is lnteriorly threaded Threaded into this In the use of the device, after the casing has been placed with the seat or disk 14 therein, the desired amount of the cement is poured into the well and the piston placed on the cement. Pump pressure is then ap- 'ed to force the piston wardly into the casing so at the sides of the sari the desired seal. en the pin orrivesat the disk, the 19 thereof panes through the opening 15 until the valve 21 solidly enga es against the valve seat 15. At this time, t e springs have ongaged the shoulders of the threads 22 and prevent return of the piston so that the seal between the valve and seat is maintained and the cement held against return to the casing. The pressure can then be removed andthe piston left in its place until the concrete and cement downieo is set, After the concrete has set, the pieton may be removed by inserting a fishing tool which williengage thereof and if the threads 22 are oppositely itched .to the threads 23 by rotating the shing tool, the disengagement of thep'stons from the springs can be obtained. therwise, it is simply necessary that astrong enough pull be exerted to break. the grip of w the springs u onthe threads 22." .The disk 14 is preferably which is readily broken by a drill so that it may be very readily drilled out of the coupling 12 by [the same pull employed for drilling the cement from the bottom of the casing. 7 It will be obvious that the disk, if so desired, can be made integralwith the casing coupling and such a structure as illustrated it in Figure 3. Since the structure is otherwise capable of modification without in any manner departin from the spirit of my invention, I do not imit myself to such specific structure except as hereinafter claimed;

I claim a I v 1. In apparatus for cementing' wells, a disk carrie by the casing adjacent the lower end thereof and havmg a central open- ,30 mg providing an upwardly facing valve seat, a follower piston adapted to upon the cement and having at its lower end a valve for coaction with the valve seat and means carried by the disk and engagin the the follower piston 'for locking the to lower p'ston in position with its valve enga ed with the seat of the disk.

2. n apparatus "for cementing'wells, a disk came by the casing adjacent the lower end thereof and having a central open- 1ng provldmg an upwardly facing valve seat, a follower piston adapted to be laced upon the cement within the casing and havmg at its lower end a valve for coaction w1th the valve seat, the piston having an axlalextension adapted for passage through the valve opening of the disk, said extension being;

he placed having upon its lower face a valve in engagement with the x, tenratchet teeth, the

lower race with thethreads 23- threads for engagement-with er end thereof formed of some material;

threads of the piston.

provided with ratchet teeth, the

wor t- I anors in the ratchet, teeth of said extension to maintain the valve in engagement with the 7 seat, the upper end of the piston having a fishing tool, 4, In apparatus for cementing wells, a disk carried by the casing adjacent the lowand having a central open ing providing an upwardly facing valve seat, a follower piston adapted to be laced upon the cement within the casing an having at its lower end a valve for coaction with the valve seat, the piston. having an axial extension ada ted for .passa e through the valve opening of the disk, said extension being rovided with ratchet teeth, the valve disk having upon its lower face a plurality of spring catches for engagement in the ratchet teeth of said extension to maintain the valve'in engagement with the seat, the upper end of the piston having threads for engagement with a fishing tool the ratchet teeth of the extension ing formed by ratchet threads, said t reads being oppositely pitched to the 5 In apparatus for cementing wells and in combination a disk adapted to be inserted in the casing of a well adjacent the lower end thereof, said disk havin a central opening formed at its upper en to provide an upwardly and outwardly tapering valve seat, a on shaped piston of substantially the same iameter asthe casing of the well in which the device is to be employed having at its lower end a teat, the junction'of the teat with the piston being formed of a valve for coaction with the seat, the teat having ratchet teeth and the bottom of the disk having spring fingers for engagement with said teeth.

6. In apparatus for cementing wellszand in combination a disk adapted to be inserted in the casin of a, well adjacent the lower end thereof, said disk having a central opening formed at its lower end to provide an upwardly and outwardly tapering valve seat, a on -shaped piston of substantially the same iameter as the easin of the well a in which the device is to be emp eyed having at its lower end a teat, the junction of the teat with the piston being. formed of a valve for coactmnwith the seat, the teat having ratchet teeth and thehottoni ol 'th'e disk having s ,ingfingers for en agement with said teeth;

the apper end of t e piston losing provided with interlor threads for engagement with a fishing tool.

ln apparatus-for cementing wells and in combination a disk adapted to he in the n of h reo dist: ed at upper end nd outwardly y apetl piston teeter the at tcentral o I l U well the lot i359 evepm in which the device is to be employed havingat its lower end a teat, the junction of the tent with the piston being formed of a valve for coaction with the seat, the teat having ratchet teeth and the bottom of the disk having spring fingers for engagement with said teeth, the upper end of the piston being provided with interior threads for engagement with a fishing tool, the ratchet teeth of the teat being providedinthe form 10 of ratchet threads oppositely pitched to the threads of the piston.

In testimony whereof I hereunto affix my signature. I

WILLIAM T. THOMAS. 

